1,544 research outputs found
Functional analysis of Hedgehog gene in amphioxus embryogenesis and mutants construction related to the Hedgehog signaling pathway
Hedgehog(Hh)基因在动物胚胎发育过程中有着重要的作用,该基因最早在果蝇中发现,参与果蝇分节极性(segmentpolarity)的形成及翅原基前后组织中心的建立;在海胆中,参与中胚层的分化;而在脊椎动物中,该基因主要参与中枢神经系统(CNS)、轴旁中胚层及附肢的发育。在头索动物文昌鱼中,前人基于Hh的表达谱分析,推测该基因参与神经管的发育及左右轴的建立,提出Hh对神经管腹侧神经元分化的作用可能是一原始特征。 本文用基因敲低、过表达和敲除3种方法对文昌鱼Hh基因在胚胎发育中的功能做了进一步研究。在敲低实验中,注射小干扰RNA可显著降低Hh基因的表达,但没有观察到胚胎发育有何异常,Hh...Hedgehog (Hh) gene first discovered in Drosophila is essential for embryogenesis and is involved in the establishment of segment polarity and A-P organizing center of the wing disc. It was shown to participate in organizing the mesoderm in sea urchin and pattern the central nervous system (CNS), paraxial mesoderm as well as limb in vertebrates. In cephalochordate, it took the roles in patterning t...学位:理学硕士院系专业:生命科学学院_遗传学学号:2162012115245
Reprogramming of global histone methylation controls the differentiation of monocytes into macrophages
单核-巨噬细胞系统由一类具有吞噬功能的免疫细胞组成,包括单核细胞、巨噬细胞及树突状细胞,是机体免疫系统重要的组成之一。来源于造血干细胞的单核细胞在趋化因子激活下,分化为巨噬细胞和树突状细胞,参与机体防卫。目前有关单核-巨噬细胞分化的细胞学过程已基本阐释,然而分化进程中关键分子及其调控网络仍需要深入阐明。此外,单核细胞如果过度增生,会导致正常造血功能衰竭。白血病的发生也与单核-巨噬细胞系统的异常发展有关。因此,深入探索和阐明单核/巨噬细胞形成过程中关键转录因子及其调控网络,为深入了解免疫系统发育及疾病发生提供重要的理论依据,并为白血病的临床诊断和治疗提供有效的分子靶点。 本研究采用了经典的佛波...Monocyte-macrophage system is a part of the immune system in higher animals, which consists a class of phagocytosis immune cells, including monocytes, macrophages and dendritic cells. Mononuclear cells derive from hematopoietic stem cells, and can differentiate into macrophages and dendritic cells, which involved in the body defense. Currently the differentiation process has been mainly explained,...学位:理学硕士院系专业:医学院_微生物学学号:2452013115344
Design and Implementation of Administrative Examination and Approval Management System Based on J2EE
随着我国经济体制的深入改革,地方政府的职能逐渐地由管理型向服务型转变,传统的地方政府管理方式发生较大变化,政府的行政审批效率逐渐变得越来越重要,传统的手工管理方式已经不能适应互联网时代的发展。加强电子政务的建设,开发行政审批管理系统对政府的建设与发展有重要的作用。行政审批管理系统能够增强政府的监管与服务能力,加快政府职能的转变、能提高政府的公众服务能力,因此开发行政审批管理系统对政府部门的管理、决策、服务等能力的提升有重要的意义。 本文基于J2EE架构,采用Java语言、JavaScript脚本技术、JSP技术和UML建模技术,以SQLServer2005数据库作为存储数据的工具,设计并实现...With the deep development of economic system reform, the functions of local government gradually changed from management to service, the traditional management patterns of local government changed greatly at all levels of government administrative efficiency becomes more and more important, the traditional manual management mode has already can't adapt to the development of the Internet era. Stren...学位:工程硕士院系专业:软件学院_工程硕士(软件工程)学号:X201323046
Study on the Role and Administration Authority of the Universities in the Employment Agreement
毕业生就业协议书作为明确毕业生与用人单位之间权利义务关系的合同,在保护毕业生就业权利过程中发挥着重要作用。但是近年来高校对自身在协议书中角色定位以及职责权利认知不明确,导致高校在特定情况下基于特定目的强制毕业生签订就业协议书或限制毕业生解约,侵犯学生就业权益的情形时有发生。其部分原因在于高校对自身的地位、享有的权利和承担的义务没有清醒的认识。因此高校在就业协议书中的角色定位、职责权利问题亟待关注。 由于协议书的性质将影响高校的角色定位,因此首先需要明确协议书的性质。本文认为就业协议书属于普通民事合同,合同的当事人为用人单位与毕业生,高校并非合同的当事人。因此高校并不能决定协议的成立、变更、解...The graduate employment agreement, as the contract specifying the rights and obligations of the graduates and the employers, plays an important role in protecting the employment rights of the graduates. But in recent years, the events such as the universities forcing the graduates to sign the employment agreement or limiting the graduates to terminate the agreement often happen owing to the univer...学位:教育学硕士院系专业:教育研究院_高等教育学学号:2572014115181
Mechanism of Latent HIV reactivation by flavonoid compound LC431
艾滋病是因感染HIV病毒而引起的一种死亡率高,传播范围广的免疫缺陷综合征。高效抗逆转录病毒疗法一度被认为是治疗HIV的良方,尽管高效抗逆转录病毒疗法可以将病毒载量降低至检测限以下,但却不能从根本上根除病毒,因为病毒颗粒会潜伏在“病毒库”中,一经停药,病毒又会“卷土重来”。因此,科学家们提出了一种新的疗法——shock&kill,就是先用激活剂将包藏在CD4+T细胞中的病毒激发出来,再联用HAART以及自身免疫系统将其一举消灭。 RNAPolⅡ是真核生物转录过程最重要的聚合酶,在转录延伸阶段,P-TEFb作为一个转录延伸因子,可以磷酸化RNAPolⅡ的CTD区域,以及负性转录因子DSIF和NE...AIDs is a kind of Immune deficiency syndrome that can cause a high rate of fatality and widely spreading, Which is caused by HIV infection. Highly active antiretroviral therapy was considered a good treatment for HIV, However, although the viral load can be reduced to lower than detection limit by HAART, It cannot fundamentally eradicate the virus. Because virus particles can hide themselves into ...学位:医学硕士院系专业:药学院_药理学学号:3232014115343
The intra-industry spillover effect of overseas M&A—— Research based on Chinese Public Firms
自中国加入WTO,经济快速增长,国内企业的国际化进程也逐渐加快,对外净投资额也在逐年增加,出境并购作为中国企业对外直接投资的主要方式之一,并购数量和并购金额也在逐年增加。中国作为最大的发展中国家,国内企业出境并购的主要动机是为了获得先进的技术、知识及管理经验,众多研究也表明出境并购确实促进了母国的技术进步,但是这些研究都集中于宏观的国家或行业层面,缺乏关于出境并购对母国相关行业内其他企业溢出效应的研究。 本文基于前人的研究,主要从以下几个方面进行拓展:一是本文从微观的角度,而非国家或行业等宏观层面,研究出境并购在母国企业层面的溢出效应。二是本文实证检验了出境并购在母国行业内水平溢出效应是否存...The process of internationalization of domestic enterprises has gradually accelerated since China accessed to WTO.As one of the main ways of OFDI in China,the number of M&As and the amount of M&As increase. As the largest developing country,the main motivation for Chinese domestic enterprises to exit M&As is to obtain advanced technology,knowledge and management experience.Studies have shown that ...学位:经济学硕士院系专业:经济学院_国际贸易学学号:1572014115193
A Study of EU’s Participation in Arctic Governance
欧盟与北极在地缘、经济等有多方面的关联性,对北极的资源价值有着极大的利益诉求。2007年,欧盟以海洋问题切入北极事务,经过2008年、2012年的两次正式的北极政策确立和完善,欧盟初步形成政策连贯、目标明确、执行性强的北极战略。欧盟的北极政策中明确了对北极治理的规划和目标,既致力于从北极公共问题如气候、海洋、环境、原住民等问题发挥自己的影响力,保障北极的生态系统平衡和可持续发展,也积极谋求在北极治理上的地位,增强在北极问题上的话语权,在北极开发治理上成为利益共享者。 总体来说,欧盟把实现自身在北极的利益诉求与推进完善北极治理有机地结合在一起,将自己塑造成应对北极问题的合作者和公共产品提供者的...EU has the geopolitical and economic correlation with the Arctic and claims great interests in arctic energy resources and shipping routes. At the beginning of Arctic competition among Arctic countries, EU started to develop the Arctic policy strategy to seek for participation in the Arctic affairs and ensure its own interests in the Arctic resources. In the year of 2008 and 2012, EU provided two ...学位:法学硕士院系专业:南洋研究院_国际关系学号:2552013115227
Professionalization of Acting in Shakespeare's England
[[notice]]本書目待補正[[conferencetype]]國內[[conferencedate]]20091126~2009112
Quantum Dots Sensitized Solar Cells Based on Chalcogenide Semiconductors
近年来,太阳能电池的研究得到迅猛发展,但是现有的新型太阳能电池仍然面临性价比低、寿命短等问题,离大规模商品化尚有一定距离。研究开发新型的高效率、低成本的太阳电池仍是当前太阳能利用领域努力的方向。其中,新一代太阳能电池——量子点敏化太阳能电池(QDSSC)由于具备高理论转换效率和低生产成本等潜在优点,正在引起研究者的广泛关注。 量子点敏化太阳能电池是一种新型太阳能电池,其制作工艺简单、价格低廉、稳定性好,是继染料敏化太阳能电池后又一与硅基太阳能电池有竞争力的电池。然而,目前QDSSC的光电转换效率仍然远低于传统太阳能电池。因此,提高QDSSC的光电转换效率是目前研究的重点。QDSSC主要由吸附...Although the efficiency of solar cells have dramatically improved in recent years, the existing new types of solar cells still do not exhibit high enough cost performance and necessary lifetimes. There is still a long way to go toward the large-scale commercialization. Therefore, to design and develop a new type solar cell with higher efficiency and lower cost has always been the aim in the resear...学位:理学硕士院系专业:化学化工学院化学系_物理化学(含化学物理)学号:2052009115140
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